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Dementia is a global public health problem with increasing prevalence and incidence worldwide. The African continent is expected to bear the biggest brunt of the burden of dementia by 2050 because of the rapid demographic changes, including rapid population growth, an increase in life expectancy, and ageing. However, French-speaking Sub-Saharan African (FS-SSA) countries are underrepresented in research on dementia in Africa. While the reasons are diverse and complex, linguistic and cultural barriers to research, disproportionately affect these countries and may be significant factors. Any efforts, therefore, to redress the burden of dementia in Africa must consider the specific demographic, cultural, and linguistic characteristics of FS-SSA countries. This scoping review explores the current state of knowledge in dementia and cognitive impairment in Sub-Saharan Africa, highlighting research gaps and specific patterns unique to FS-SSA Africa. We identify pathways for research to bridge the knowledge gaps on dementia in FS-SSA as part of the global endeavor to tackle dementia worldwide.

Human African trypanosomiasis (HAT) remains a serious public health problem with diagnostic and treatment challenges in many African countries. The absence of a gold-standard biomarker has been a major difficulty for accurate disease staging and treatment follow-up. We therefore attempted to develop a simple, affordable, and noninvasive biomarker for HAT diagnosis and staging. Simultaneous actigraphy and polysomnography as well as cerebrospinal fluid (CSF) white blood cell (WBC) count, trypanosome presence, and C-X-C motif ligand (CXCL)-10 cytokine levels were performed in 20 HAT patients and nine healthy individuals (controls) using standard procedures. The International HIV Dementia Scale (IHDS) was scored in some patients as a surrogate for clinical assessment. From actigraphic parameters, we developed a novel sleep score and used it to determine correlations with other HAT markers, and compared their performance in differentiating between patients and controls and between HAT stages. The novel actigraphy sleep score (ASS) had the following ranges: 0–25 (healthy controls), 67–103 (HAT stage I), 111–126 (HAT intermediate), and 133–250 (HAT stage II). Compared with controls, stage I patients displayed a 7-fold increase in the ASS (P < 0.01), intermediate stage patients a 10-fold increase (P < 0.001), and HAT stage II patients an almost 20-fold increase (P < 0.001). CXCL-10 showed high interindividual differences. White blood cell counts were only marked in HAT stage II patients with a high interindividual variability. The International HIV Dementia Scale score negatively correlated with the ASS. We report the development and better performance of a new biomarker, ASS, for HAT diagnosis, disease staging, and monitoring that needs to be confirmed in large cohort studies.

Background. Sleep apnea syndrome (SAS), a growing public health threat, is an emerging condition in sub-Saharan Africa (SSA). Related SSA studies have so far used an incomplete definition. This study is aimed at assessing SAS using an American Academy of Sleep Medicine (AASM) complete definition and at exploring its relationship with comorbidities, among patients hospitalized in a Cameroonian tertiary hospital. Methods. This cross-sectional study was conducted in cardiology, endocrinology, and neurology departments of the Yaoundé Central Hospital. Patients aged 21 and above were consecutively invited, and some of them were randomly selected to undergo a full night record using a portable sleep monitoring device, to diagnose sleep-disordered breathing (SDB). SAS was defined as an apnea − hypopnea index AHI ≥ 5 /h, associated with either excessive daytime sleepiness or at least 3 compatible symptoms. Moderate to severe SAS (MS-SAS) stood for an AHI ≥ 15 / h . We used chi-square or Fisher tests to compare SAS and non-SAS groups. Findings. One hundred and eleven patients presented a valid sleep monitoring report. Their mean age ± standard deviation (range) was 58 ± 12.5 (28–87) years, and 53.2% were female. The prevalence (95% confident interval (CI)) of SAS was 55.0 (45.7, 64.2)% and the one of MS-SAS 34.2 (25.4, 43.1)%. The obstructive pattern (90.2% of SAS and 86.8% of MS-SAS) was predominant. The prevalence of SAS among specific comorbidities ranged from 52.2% to 75.0%. Compared to SAS free patients, more SAS patients presented with hypertension (75.4% vs. 48.0%, p = 0.005 % ), history of stroke (36.7% vs. 32.0%, p = 0.756 ), cardiac failure (23.0% vs. 12.0%, p = 0.213 ), and combined cardiovascular comorbidity (80.3% vs. 52.0%, p = 0.003 ). Similar results were observed for MS-SAS. Metabolic and neuropsychiatric comorbidities did not differ between SAS and SAS-free patients. Conclusion. The SAS diagnosed using modified AASM definition showed high prevalence among patients hospitalized for acute medical conditions, as it was found with SDB. Unlike HIV infection, metabolic and brain conditions, cardiovascular comorbidities (hypertension and cardiac failure) were significantly more prevalent in SAS patients.

Energy metabolism is tightly linked with circadian rhythms, exposure to ambient light, sleep/wake, fasting/eating, and rest/activity cycles. External factors, such as shift work, lead to a disruption of these rhythms, often called circadian misalignment. Circadian misalignment has an impact on some physiological markers. However, these proxy measurements do not immediately translate into major clinical health outcomes, as shown by later detrimental health effects of shift work and cardio-metabolic disorders. This review focuses on the effects of shift work on circadian rhythms and its implications in cardio-metabolic disorders and eating patterns. Shift work appears to be a risk factor of overweight, obesity, type 2 diabetes, elevated blood pressure, and the metabolic syndrome. However, past studies showed discordant findings regarding the changes of lipid profile and eating patterns. Most studies were either small and short lab studies, or bigger and longer cohort studies, which could not measure health outcomes in a detailed manner. These two designs explain the heterogeneity of shift schedules, occupations, sample size, and methods across studies. Given the burden of non-communicable diseases and the growing concerns about shift workers’ health, novel approaches to study shift work in real contexts are needed and would allow a better understanding of the interlocked risk factors and potential mechanisms involved in the onset of metabolic disorders.

Functional connectivity between cerebral cortical regions during natural sleep has attracted a keen interest from both cognitive and clinical neuroscientists because of its importance in understanding the default mode network of human brain. Multiple recordings of functional near-infrared spectroscopy (fNIRS) in several sleep phases make it possible for us to detect potential differences of directional interactions between cortical areas from healthy subjects and patients with ADHD or sleep disorders. Namely we propose a computational method to estimate time-domain Granger causality among fNIRS time series using a Kolmogorov–Smirnov test based on F-statistics. In order to validate indication of directional interactions, we also apply convergent cross-mapping to the time series as an alternative approach to causality based on state space reconstruction of dynamical systems. Comparing the averaged heatmaps of significant causal pairs of regions, we show that the map of directional interactions varies for each sleep phase, e.g., REM, of the same subject. The observation suggests an unexplored source for non-invasive classification benchmark of the above cognitive disorders.

BackgroundThe COVID-19 pandemic has been associated with significant psychological and social distress worldwide. We investigated fear and depression among adults in Cameroon during different phases of the COVID-19 outbreak.MethodsAn online survey was conducted in Cameroon from June–December 2020 using a structured questionnaire. Socio-demographic data and information regarding COVID-19 history were obtained. Fear and depressive symptoms were assessed using the Fear of COVID-19 score (FCV-19S) and the Patient Health Questionnaire (PHQ-9), respectively. Responses were clustered in weeks to better appreciate their evolution over time.ResultsOverall, 7381 responses from all ten regions of Cameroon were analysed (median age: 30 years, 73.3% male). The prevalence of depression (PHQ-9 score ≥ 10) was 8.4%, and that of high fear of COVID-19 (FCV-19S scores ≥19) was 57.4%. These rates were similar across genders, age-groups, and region of residence. While mean weekly PHQ-9 scores remained fairly stable throughout the study period (range: 2.53–3.21;p = 0.101), mean FCV-19S scores were highest during the early weeks but decreased significantly thereafter (from 20.31 to 18.34;p ConclusionDepression amidst the COVID-19 crisis is less prevalent in Cameroon than in other countries. Prompt and widespread dissemination of adequate COVID-19 information may reduce the risks for depression by dispelling fear and anxiety among Cameroonians.

The use of screen electronic devices in the evening negatively affects sleep. Yet, sleep is known to be essential for brain maturation and a key factor for good academic performance, and thus is particularly critical during childhood and adolescence. Although previous studies reported associations between screen time and sleep impairment, their causal relationship in adolescents remains unclear. Using actigraphy and daily questionnaires in a large sample of students (12 to 19 years old), we assessed screen time in the evening and sleep habits over 1 month. This included a 2 week baseline phase, followed by a 40 min sleep education workshop and a 2 week interventional phase, in which participants were asked to stop using screen devices after 9 pm during school nights. During the interventional phase, we found that the reduction of screen time after 9 pm correlated with earlier sleep onset time and increased total sleep duration. The latter led to improved daytime vigilance. These findings provide evidence that restricting screen use in the evening represents a valid and promising approach for improving sleep duration in adolescents, with potential implications for daytime functioning and health.

Background: Cameroon was not spared by the coronavirus 2019 (COVID-19) pandemic, prompting the Cameroonian government to implement nationwide measures to stall viral transmission. However little is known about how well these unprecedented measures are being observed as the pandemic evolves. Methods: We conducted a six-month online survey to assess the preventive behaviour of Cameroonian adults during the COVID-19 outbreak. Sociodemographic data and personal history of respondents were obtained, and a 5-point adherence score was constructed based on self-reported observance of the following preventive measures: physical distancing, face mask use, hand hygiene, not touching one’s face, and covering the mouth when coughing or sneezing. Predictors of adherence were investigated using ordinal logistic regression models. Findings: Overall, 7,381 responses from all ten regions of Cameroon were analysed (mean age: 32·8±10·8; 73·3% male). During the two weeks preceding participation in the survey, 20 of the 496 tested respondents were positive for COVID-19 (positivity rate: 4·0%). Overall mean adherence score was 3·96±1·11 on a scale of 0–5. Mean weekly adherence scores were initially high, but gradually decreased over time accompanied by increasing incidence of COVID-19 during the last study weeks. Multivariable analyses revealed that older persons, those receiving COVID-19 information from health personnel, and those who agreed with the necessity of lockdown measures had higher odds for adherence, while experiencing flu-like symptoms was associated with poor adherence. Interpretation: Pending more permanent solutions like large scale COVID-19 vaccination, continuous observance of preventive measures should be encouraged among Cameroonians to avoid a resurgence in COVID-19 infections. Funding Statement: ERC Advanced Grant (671055) and VLIRUOS (Flemish University cooperation). Declaration of Interests: The authors have no conflicts of interest to declare. Ethics Approval Statement: This study was approved by the National Ethics Committee of Cameroon (Ref: 2020/05/1229/CE/CNERSH/SP of 06.5.20) as well as the Ethics Committee of the University of Antwerp, Belgium (Ref: 20/13/148).

Sleepwalkers' complex nocturnal behaviors have inspired fictional characters from Shakespeare's Lady Macbeth to Polidori's Vampyre to Cesare, the homicidal somnambulist in The Cabinet of Dr Caligari. Yet although the underlying pathophysiology of sleepwalking, i.e. the partial arousal from slow-wave sleep, is today well-documented, the detailed sensorimotor mechanisms permitting locomotion and further complex behaviors to occur outside of conscious control remain poorly understood [1]. Further, the paroxysmal character, nocturnal pattern, and spontaneous onset have made it nigh on impossible to study somnambulism behaviorally during wakefulness. The goal-directed walking paradigm reported here, based on full-body motion capture and virtual reality feedback, directly addresses this issue and provides unique insights into the functional mechanisms of this common parasomnia: sleepwalkers exhibited improved movement automation and a stronger dissociation between locomotor control and awareness than matched controls when challenged with a cognitive load. Our data therefore suggest that behavioral markers exist in awake sleepwalkers, characterized by their ability to perform complex locomotor actions in the absence of full consciousness. Our findings are important as they firmly link sleepwalking to the neuroscience of motor control and motor awareness and may complement formal diagnosis procedures (normally requiring time, cost-intensive sleep studies and polysomnographic recordings).

The use of screen electronic devices (SED) in the evening negatively affects sleep. Yet, sleep is known to be essential for brain maturation and a key factor for good academic performance, and thus is particularly critical during childhood and adolescence. While previous studies reported correlations between SED use and sleep impairments, the causal relationship between SED use and sleep in adolescents remains unclear. Using actigraphy and daily questionnaires in a large sample of students (12 to 19 years old), we assessed SED use and sleep habits over one month, including a two-week baseline phase and a two-week interventional phase, where participants were asked to stop screen use after 9 pm during pre-school nights. During the interventional phase, we found that reduction in time spent on SED after 9 pm correlated with earlier sleep onset time and increased total sleep duration. The latter led to improved daytime vigilance. We also observed that the beneficial impact of the intervention on sleep was influenced by catechol-O-methyltransferase gene (COMT) Val158Met polymorphism, which is implicated in the dopaminergic modulation of human behaviors, including wake and sleep regulation. These findings provide evidence that restricting SED use in the evening represents a valid and promising approach for improving sleep duration in adolescents, with potential implications for daytime functioning and health.STATEMENT OF SIGNIFICANCEWith the emergence of smartphones and other connected devices, adolescents spend a lot of time on screen electronic devices (SED), especially during the evening. We report that time spent on SED after 9 pm negatively correlates with sleep onset time, sleep duration as well as mood, body weight, and academic performance. Such observable correlations urge for educational strategies to address the chronic lack of sleep observed in today’s adolescent populations. Here we also show that limiting the use of SED after 9 pm improves sleep duration and daytime vigilance in most adolescents. This simple education recommendation pertaining to sleep hygiene can be implemented by every household, yielding direct positive effects on sleep, and presumed benefits for health and daytime functioning.

Coexisting central and obstructive sleep apnea is a challenging clinical situation. We report a case exhibiting an overnight shift from obstructive to central events. The central sleep apnea component was related to sleep instability, hyperventilation and low nocturnal PaCO2. Both types of respiratory events were successfully treated with adaptive servoventilation.

highlights This study shows that the patients with primary sleep onset insomnia (SOI) and sleep maintenance insomnia (SMI) present different spectral characteristics during sleep onset period. The lower level of beta (18-29.75 Hz) frequency band found in SOI in comparison with SMI suggests that the hyperarousal is not involved in the etiology of primary sleep onset insomnia. The results of the current study seem to corroborate a ''wake-sleep switch problem'' as a basic mech- anism of SOI. abstract Objective: To compare the EEG power spectra characteristics of the sleep onset period (SOP) in patients with sleep onset insomnia (SOI), sleep maintenance insomnia (SMI) and good sleepers (GS). Methods: The time course of EEG power density (1-40 Hz) during the SOP was examined in thirty sub- jects (SOI patients: N = 10, SMI patients: N = 10, GS: N = 10). Results: The EEG power of the beta2 frequency band (18-29.75 Hz) was significantly lower in SOI than in SMI in the period preceding sleep onset. The alpha power was significantly higher for the SMI group com- pared to GS before sleep onset. Despite the lack of statistical significance, several differences in EEG dynamics were observed in SOI compared to two other groups: delta power increased slower after sleep onset; beta2 and 3 (18-29.75 and 30-39.75 Hz) power decrease less abruptly before sleep onset; beta1 (15-17.75 Hz) power increase through the whole SOP. Conclusions: The lower level of beta2 frequency band in SOI and the differences in dynamics in delta and beta bands may suggest that a mechanism other than hyperarousal participates in etiology of SOI. Significance: SOI and SMI patients have different spectral characteristics in SOP, thus future studies should avoid the inclusion of mixed insomnia samples.

Les troubles du sommeil sont frequents dans la population geriatrique etant souvent interpretes comme partie integrante du processus de vieillissement. En effet, l’architecture du sommeil change avec l’âge, neanmoins l’âge lui-meme ne doit pas etre considere comme a l’origine des troubles du sommeil. Une plainte de sommeil, qu’elle soit quantitative ou qualitative, doit declencher le depistage de certaines maladies qui sont plus prevalentes chez les personnes âgees et qui peuvent beneficier d’une prise en charge specifique.

A scalable hardware/software hybrid module--called Ubidule--endowed with bio-inspired ontogenetic and epigenetic features is configured to run a neural networks simulation with developmental and evolvable capabilities. We simulated the activity of hierarchically organized spiking neural networks characterized by an initial developmental phase featuring cell death followed by spike timing dependent synaptic plasticity in presence of background noise. An upstream 'sensory' network received a spatiotemporally organized external input and downstream networks were activated only via the upstream network. Precise firing sequences, formed by recurrent patterns of spikes intervals above chance levels, were observed in all recording conditions, thus suggesting the build-up of a connectivity able to sustain temporal information processing. The activity of a Ubinet--a network of Ubidules--is analyzed by means of virtual electrodes that recorded neural signals similar to EEG. The analysis of these signals was compared with a small set of human recordings and revealed common patterns of shift in quadratic phase coupling. The results suggest some interpretations of changes and plasticity of functional interactions between cortical areas driven by external stimuli and by learning/cognitive

Transient loss of consciousness (T-LOC) with abnormal posture or movements reflects a temporary dysfunction of the brain, either primary or secondary. In a period of high technological medical access, patients with T-LOC constitute a challenge to improve the medical "art of listening." The difficulty in dealing with isolated paroxysmal phenomena is associated with the probability of the occurrence of a second event and therefore the entrance of the patient into a chronic disorder. We present a detailed analysis of symptoms that should help the general practitioner in the differential diagnosis among three main entities in the adult populations: syncope, epileptic seizure, and psychogenic seizure (dissociative convulsion).

The possibility of combining the high spatial resolution of functional magnetic resonance imaging (fMRI) with the high temporal resolution of electroencephalography (EEG) may provide a new tool in cognitive neurophysiology, as well as in clinical applications such as epilepsy. However, the simultaneous recording of EEG and fMRI raises important practical problems: 1) the patients' safety, in particular the risk of skin burns due to electrodes heating; 2) the impairment of the EEG recording by the static magnetic field, as well as by RF and magnetic field gradients used during MRI; and 3) the quality of MR images, which may be affected by the presence of conductors and electronic devices in the MRI bore. Here we present our experiences on 19 normal volunteers who underwent combined fMRI and 16-channel EEG examination. Consistent with previous reports, safety could be assured when performing EEG recordings during fMRI acquisition. Electrophysiological signals recorded with surface EEG were similar inside and outside the 1.5 T magnet. Furthermore, fMRI using motor or visual tasks revealed similar areas of activation when performed with and without 16-channel EEG recording. J. Magn. Reson. Imaging 2001;13:943-948.

Unilateral spatial neglect entails a failure to detect or respond to stimuli in the space opposite to a brain lesion. However, the contralesional hemispace can be determined by different frames of spatial coordinates, such as eyes-, head-, body-, or environment-centered coordinates. We observed 2 patients with a right hemisphere stroke whose left spatial neglect was modulated by distinct coordinates systems depending on the task. Four tasks were given in different conditions of central gaze and either the eyes or the head rotated 30° to the right or 30° to the left. While the 2 patients had a retinotopic defect in 1 visual field quadrant that remained the same irrespective of gaze direction (upper or lower quadrant in 1 case each), the other quadranopic field defect improved with eyes rotation to the right but not with head rotation, suggesting a head-centered spatiotopic deficit. Performance on line bisection was influenced both by eyes and head rotation, as well as by the position of the lines with respect to the trunk midline, suggesting the involvement of both head-centered and body-centered coordinates. Visual imagery and auditory extinction were not modified by changing the eyes or head position. These findings suggest that distinct spatial coordinates are brought into play depending on the tasks demands. (JINS, 1999, 5, 75–82.)

There are some arguments that Friedrich Nietzsche suffered from the autosomal dominant vascular microangiopathy: Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL). Here, a hypothesis is formulated supporting that CADASIL presenting with symptoms of bipolar disorder and Gastaut-Geschwind syndrome would contribute to the increased insight and creativity of a philosopher whose perceptions and intuitions often bear out the results of modern neuroscience. Alterations of the brain default and reward networks would account for such an increased level of introspection and creativity. A new framework on approaching illness is proposed, which, in conformity with Nietzsche's positive view, outlines the enabling aspects of some otherwise highly disabling neuropsychiatric disorders.

Consciousness remains an ill-defined concept. This is reflected in clinical practice as there is no objective way to determine that an unresponsive patient is aware of himself and his/her surroundings. However, from the correct answer to this question depends the diagnosis and eventually the continuation of life sustaining aid. Here we discuss how to build on top of recent progress in the field of reverse neural engineering to implement a Test able to detect objective markers of consciousness for completely unresponsive patients. By focusing on the so-called “soft problem of consciousness”—the correlation between the brain and mental functions—we briefly sketch how we plan to provide partial answers the following questions: (1) What are the necessary conditions to confirm that a conscious mind is enclosed in a completely paralyzed body?, (2) How can we extract these responses from neural activity alone?, (3) How could these signals be exploited to establish a minimal dialogue between the patient and a physician using a system that interprets the neural responses?, (4) Is awareness localized to certain neural structures or, instead, is it a global process that depends on the activation of a critical mass of neurons?

Introduction We report a case of postural tachycardia syndrome occurring after the surgical correction of an aortic coarctation, and coexisting with upper airway resistance syndrome. Case presentation A 29-year-old Caucasian man complained of extreme fatigue, daytime sleepiness, shortness of breath on exertion, light-headedness and general weakness on standing. These symptoms began shortly after the surgical correction of an aortic coarctation and became progressively more debilitating, impairing any daily activity. An extensive work-up revealed postural tachycardia syndrome and a coexisting sleep-related breathing disorder, characterized as upper airway resistance syndrome. Conclusion This is the first reported case describing the occurrence of postural tachycardia syndrome after the surgical correction of an aortic coarctation. This case also provides evidence for the suggestion that this syndrome may coexist with upper airway resistance syndrome, although the exact nature of their relationship must still be better established.

Background Human African trypanosomiasis (HAT) or sleeping sickness leads to a complex neuropsychiatric syndrome with characteristic sleep alterations. Current division into a first, hemolymphatic stage and second, meningoencephalitic stage is primarily based on the detection of white blood cells and/or trypanosomes in the cerebrospinal fluid. The validity of this criterion is, however, debated, and novel laboratory biomarkers are under study. Objective clinical HAT evaluation and monitoring is therefore needed. Polysomnography has effectively documented sleep-wake disturbances during HAT, but could be difficult to apply as routine technology in field work. The non-invasive, cost-effective technique of actigraphy has been widely validated as a tool for the ambulatory evaluation of sleep disturbances. In this pilot study, actigraphy was applied to the clinical assessment of HAT patients. Methods/Principal Findings Actigraphy was recorded in patients infected by Trypanosoma brucei gambiense, and age- and sex-matched control subjects. Simultaneous nocturnal polysomnography was also performed in the patients. Nine patients, including one child, were analyzed at admission and two of them also during specific treatment. Parameters, analyzed with user-friendly software, included sleep time evaluated from rest-activity signals, rest-activity rhythm waveform and characteristics. The findings showed sleep-wake alterations of various degrees of severity, which in some patients did not parallel white blood cell counts in the cerebrospinal fluid. Actigraphic recording also showed improvement of the analyzed parameters after treatment initiation. Nocturnal polysomnography showed alterations of sleep time closely corresponding to those derived from actigraphy. Conclusions/Significance The data indicate that actigraphy can be an interesting tool for HAT evaluation, providing valuable clinical information through simple technology, well suited also for long-term follow-up. Actigraphy could therefore objectively contribute to the clinical assessment of HAT patients. This method could be incorporated into a clinical scoring system adapted to HAT to be used in the evaluation of novel treatments and laboratory biomarkers., Author Summary The clinical picture of the parasitic disease human African trypanosomiasis (HAT, also called sleeping sickness) is dominated by sleep alterations. We here used actigraphy to evaluate patients affected by the Gambiense form of HAT. Actigraphy is based on the use of battery-run, wrist-worn devices similar to watches, widely used in middle-high income countries for ambulatory monitoring of sleep disturbances. This pilot study was motivated by the fact that the use of polysomnography, which is the gold standard technology for the evaluation of sleep disorders and has greatly contributed to the objective identification of signs of disease in HAT, faces tangible challenges in resource-limited countries where the disease is endemic. We here show that actigraphy provides objective data on the severity of sleep-wake disturbances that characterize HAT. This technique, which does not disturb the patient's routine activities and can be applied at home, could therefore represent an interesting, non-invasive tool for objective HAT clinical assessment and long-term monitoring under field conditions. The use of this method could provide an adjunct marker of HAT severity and for treatment follow-up, or be evaluated in combination with other disease biomarkers in body fluids that are currently under investigation in many laboratories.

Recordings of brain electrophysiological activity provide the most direct reflect of neural function. Information contained in these signals varies as a function of the spatial scale at which recordings are done: from single cell recording to large scale macroscopic fields, e.g., scalp EEG. Microscopic and macroscopic measurements and models in Neuroscience are often in conflict. Solving this conflict might require the developments of a sort of bio-statistical physics, a framework for relating the microscopic properties of individual cells to the macroscopic or bulk properties of neural circuits. Such a framework can only emerge in Neuroscience from the systematic analysis and modeling of the diverse recording scales from simultaneous measurements. In this article we briefly review the different measurement scales and models in modern neuroscience to try to identify the sources of conflict that might ultimately help to create a unified theory of brain electromagnetic fields. We argue that seen the different recording scales, from the single cell to the large scale fields measured by the scalp electroencephalogram, as derived from a unique physical magnitude--the electric potential that is measured in all cases--might help to conciliate microscopic and macroscopic models of neural function as well as the animal and human neuroscience literature.

Continuous electroencephalogram in the intensive care unit is increasingly recognized as an important diagnostic and prognostic tool in critically ill patients. Metal disc electrodes or subdermal needle electrodes are neither computed tomography nor magnetic resonance imaging compatible. Their frequent replacement required for imaging purposes is time consuming and contributes to scalp breakdown. We have developed and report on two new types of imaging compatible electrodes. The subdermal wire electrode and the silver-epoxy-coated conductive plastic electrode are magnetic resonance imaging, computed tomography, and angiogram compatible. Moreover, the subdermal wire electrode does not require any daily maintenance. The electrodes were used on a total of 24 intensive care unit patients (subdermal wire electrode = 20, conductive plastic electrodes = 4) who required continuous electroencephalogram. During an average of 62.2 +/- 44 hours of electroencephalogram recording, 54% of the patients underwent imaging procedures (nine magnetic resonance imagings, five computed tomographic scans, and two angiograms) of good quality without the need to remove/replace the electrodes. The continuous electroencephalogram revealed epileptogenic activity that was not detected on standard 20-minute recordings in 28% of patients screened, with electrographic seizures in 11%. These two types of imaging compatible electrodes offer definite advantages in clinical practice. The combined diagnostic information of continuous electroencephalogram and easy-to-plan imaging yields important results and improves the clinical management and treatment of intensive care unit patients.

Transient loss of consciousness (T-LOC) with abnormal posture or movements reflects a temporary dysfunction of the brain, either primary or secondary. In a period of high technological medical access, patients with T-LOC constitute a challenge to improve the medical "art of listening." The difficulty in dealing with isolated paroxysmal phenomena is associated with the probability of the occurrence of a second event and therefore the entrance of the patient into a chronic disorder. We present a detailed analysis of symptoms that should help the general practitioner in the differential diagnosis among three main entities in the adult populations: syncope, epileptic seizure, and psychogenic seizure (dissociative convulsion).

Drug-induced seizures are an uncommon complication of drug therapy. The drug related factors are either the intrinsic epileptogenicity of the specific agent or patient related factors such as convulsive predisposition, underlying neurologic dysfunction, and factors which affect the serum concentration and/or central neurologic system concentrations. Some anti epileptic drugs may aggravate an epileptic syndrome. In 10-15% of patients with epilepsy, better control of seizures can be achieved with combination therapy. These patients are at greater risk of suffering clinically serious interactions. Drug interactions occur at the pharmacokinetic level and at the pharmacodynamic level, involving synergistic or antagonistic effects. Finally many drugs can interfere with the antiepileptic drug metabolism. The inverse effect is also frequent. A better knowledge of the spectrum of drugs that cause seizures or interfere with antiepileptic drugs metabolism is important for evaluation of appropriate treatment options and for guiding the choice of rational therapeutic procedures.

Publisher Summary This chapter discusses the problem of bimanual coordination as human skills typically require the cooperation of both the hands. The precision in this spatial and temporal bimanual cooperation raises the question of how the two brain hemispheres cope with the problem of bimanual coordination. The study of a complex bimanual and goal-oriented synergy revealed deterministic behavior in goal achievement, whereas looking at right-hand or left-hand constituents, a more probabilistic behavior was found. It is found that the examined bimanual and goal-directed synergy has the connotation of a system characterized by its temporal invariance in spite of the variability of its components. The chapter suggests that in the overall control of complex synergies, low-level pattern generators may be usefully included as building bricks of the synergy. The presence of assimilation effects, division of labor, and end-point control in the same task, argues for combined heterarchic and hierarchic organizational principles.

The issue of bimanual temporal coordination in human subjects is discussed for three selected movement paradigms: (i) simple, symmetric, bimanual finger movements, (ii) bimanual unloading, and (iii) a complex bimanual pull and grasp task. Temporal synchronization was found for all three experiments and was least variable for the first experiment. In the second experiment, synchronization concerned unloading with the index finger of one hand (electromyographic activation of the first dorsal interosseus muscle) and the postural adjustment of the load-bearing index finger of the other hand (electromyographic deactivation of the first dorsal interosseus muscle). In the third experiment, a goal-related temporal invariance was observed, even in the absence of visual guidance. Possible neural mechanisms for the observed temporal coordination of the three types of bimanual movements are discussed, as well as the concepts of goal invariance and motor equivalence.Key words: bimanual coordination, temporal invariance, motor equivalence.